Sensor device and electronic apparatus

ABSTRACT

A sensor device includes a mounting member having fixation surfaces inside, and at least one electronic component directly or indirectly fixed to the fixation surfaces of the mounting member, and the mounting member constitutes a part of a casing for housing the electronic component. Further, the fixation surfaces are perpendicular to each other.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a continuation patent application of U.S. application Ser. No.16/135,510 filed Sep. 19, 2018, which is a divisional patent applicationof U.S. application Ser. No. 14/596,853 filed Jan. 14, 2015, now U.S.Pat. No. 10,107,653 issued Oct. 23, 2018, which is a continuation patentapplication of U.S. application Ser. No. 13/545,075 filed Jul. 10, 2012,now U.S. Pat. No. 8,960,000 issued Feb. 24, 2015, which claims priorityto Japanese Patent Application No. 2011-154502, filed Jul. 13, 2011, allof which are expressly incorporated by reference herein in theirentireties.

BACKGROUND 1. Technical Field

The present invention relates to a sensor device and an electronicapparatus.

2. Related Art

There is known such a sensor unit (sensor device) as disclosed in, forexample, U.S. Pat. No. 7,040,922 (Document 1). The sensor unit describedin Document 1 has a mounting member having a cuboid shape and threesurfaces perpendicular to each other, and sensor devices mountedrespectively on the three surfaces.

In the case of mounting such sensor devices on a circuit board or thelike, it is difficult to mount the sensor devices directly on thecircuit board, and the sensor devices are generally mounted in acondition of being housed in a casing composed of a pedestal and a lidmember. However, if the sensor devices are housed in such a casing,there arises a problem of growth in size of the sensor devices. Further,if the sensor devices are fixed obliquely to the casing, there alsoarises a problem that the detection axes of the sensor devices aretilted to thereby degrade the detection accuracy. Therefore, the sensordevices downsizing of which can be achieved, and positioning of which isperformed correctly have eagerly been desired.

SUMMARY

An advantage of the invention is to provide a sensor device and anelectronic apparatus with which positioning of a sensor component can beperformed with ease and accuracy while achieving downsizing.

An aspect of the invention is directed to a sensor device including amounting member having a space formed inside, and a fixation surfaceexposed to the space, and a plurality of electronic components includinga plurality of sensor components and fixed on the fixation surface sideof the mounting member, the sensor components have respective detectionaxes intersecting with each other, and the mounting member constitutes apart of a casing housing the electronic components.

According to this configuration, it is possible to provide a sensordevice with which positioning of a sensor component can be performedwith ease and accuracy while achieving downsizing.

In the sensor device of the above aspect of the invention, it ispreferable that the mounting member has a main body and a recessedsection opened in an outer peripheral surface of the main body.

According to this configuration, the configuration of the mountingmember becomes simple.

In the sensor device of the above aspect of the invention, it ispreferable that the fixation surface includes at least a first fixationsurface, a second fixation surface, and a third fixation surfaceintersecting with each other, and the sensor components are fixedrespectively on the first fixation surface side, the second fixationsurface side, and the third fixation surface side.

According to this configuration, the sensor device capable of detectingphysical quantities around respective three axes intersecting with eachother can be obtained.

In the sensor device of the above aspect of the invention, it ispreferable that the casing has the mounting member, and a lid membermounted above the recessed section of the mounting member.

According to this configuration, infiltration of dust or the like intothe casing can be prevented.

In the sensor device of the above aspect of the invention, it ispreferable that the mounting member has a main body and a through holepenetrating the main body.

According to this configuration, the configuration of the mountingmember becomes simple.

In the sensor device of the above aspect of the invention, it ispreferable that the fixation surface includes a first fixation surfaceand a second fixation surface intersecting with each other.

According to this configuration, the detection axes of the sensorcomponents can be made perpendicular to each other.

In the sensor device of the above aspect of the invention, it ispreferable that the casing includes a first lid member adapted to coverone opening of the through hole, and a second lid member adapted tocover the other opening.

According to this configuration, infiltration of dust or the like intothe casing can be prevented.

In the sensor device of the above aspect of the invention, it ispreferable that an inner surface of the first lid member exposed to thethrough hole intersects with the first fixation surface and the secondfixation surface.

According to this configuration, it is possible to fix the sensorcomponent also to the inner surface, and the freedom of arrangement ofthe sensor components is enhanced.

In the sensor device of the above aspect of the invention, it ispreferable that the fixation surface has a recessed section, and thesensor component is housed in the recessed section.

According to this configuration, it is possible to effectively use thespace of the mounting member to thereby achieve the downsizing of thesensor device.

In the sensor device of the above aspect of the invention, it ispreferable that the sensor components are mounted on amounting board,the mounting board includes a plurality of boards on which theelectronic components are mounted, and the plurality of boards arebendable between the boards.

According to this configuration, the fixation of the sensor componentsto the fixation surfaces becomes easy.

Another aspect of the invention is directed to an electronic apparatusincluding any of the sensor devices described above.

According to this configuration, an electronic apparatus capable ofexerting excellent reliability can be obtained.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described with reference to the accompanyingdrawings, wherein like numbers reference like elements.

FIG. 1 is a perspective view showing a sensor device according to afirst embodiment of the invention.

FIG. 2 is a cross-sectional view of the sensor device shown in FIG. 1.

FIGS. 3A and 3B are development diagrams of a mounting board provided tothe sensor device shown in FIG. 1.

FIG. 4 is a plan view showing an example of an angular velocity sensorprovided to the sensor device shown in FIG. 1.

FIG. 5 is a cross-sectional view showing a sensor device according to asecond embodiment of the invention.

FIG. 6 is a cross-sectional view of a sensor device according to a thirdembodiment of the invention.

FIGS. 7A and 7B are development diagrams of a mounting board provided tothe sensor device shown in FIG. 6.

FIG. 8 is a cross-sectional view showing a modified example of thesensor device shown in FIG. 6.

FIG. 9 is a diagram showing an example of a configuration of anelectronic apparatus equipped with the sensor device according to theinvention.

DESCRIPTION OF EXEMPLARY EMBODIMENTS

Hereinafter, a sensor device and an electronic apparatus according tothe invention will be explained in detail based on some exemplaryembodiments shown in the accompanying drawings.

1. Sensor Device

First Embodiment

Firstly, a sensor device according to a first embodiment of theinvention will be explained.

FIG. 1 is a perspective view showing the sensor device according to thefirst embodiment of the invention, FIG. 2 is a cross-sectional view ofthe sensor device shown in FIG. 1, FIGS. 3A and 3B are developmentdiagrams of a mounting board provided to the sensor device shown in FIG.1, and FIG. 4 is a plan view showing an example of an angular velocitysensor provided to the sensor device shown in FIG. 1. It should be notedthat the explanation will hereinafter be presented defining the upperside of FIG. 1 as the “upper side” and the lower side thereof as the“lower side” for the sake of convenience of explanation. Further, asshown in FIG. 1, three axes perpendicular to each other are defined asan “x axis,” a “y axis,” and a “z axis,” respectively. The z axis is anaxis parallel to the thickness direction of a pedestal 4, the x axis isan axis parallel to the extending direction of a pair of sides of thepedestal opposed to each other, and the y axis is an axis parallel tothe extending direction of the other pair of sides of the pedestalopposed to each other.

Further, hereinafter, the direction parallel to the x axis is defined asan “x-axis direction,” the direction parallel to the y axis is definedas a “y-axis direction,” and the direction parallel to the z axis isdefined as a “z-axis direction.” Further, a plane including the x axisand the y axis is defined as an “x-y plane,” a plane including the yaxis and the z axis is defined as a “y-z plane,” and a plane includingthe z axis and the x axis is defined as a “x-z plane.”

A sensor device 1 is a three-axis gyro sensor device provided withangular velocity sensors 711, 712, and 713, and capable of detectingangular velocities around the x axis, the y axis, and the z axisperpendicular to each other, respectively. Such a sensor device 1 asdescribed above is superior in convenience, and can preferably be used,for example, for motion trace, motion tracking, a motion controller, andpedestrian dead reckoning (PDR).

As shown in FIGS. 1 and 2, such a sensor device 1 as described above hasa mounting board 2 on which electronic components 7 are mounted, and acasing 10 for housing the mounting board 2. Hereinafter, each of thesemembers will sequentially be explained.

Mounting Board 2

The mounting board 2 is a rigid-flexible board obtained by combiningrigid boards (substrates) hard and difficult to be deformed, andflexible boards soft, easy to be deformed, and provided withflexibility. The mounting board 2 is arranged to be able to be bent inportions between the rigid boards. As such a mounting board 2 asdescribed above, there can be used a rigid-flexible board known to thepublic, for example, those having hard layers such as glass epoxy boardsbonded to both sides of the flexible board, and using these parts as therigid boards.

FIG. 3A is a plan view of the mounting board 2 in a developed stateviewed from one surface side, and FIG. 3B is a plan view of the mountingboard 2 in the developed state viewed from the other surface side. Asshown in FIGS. 3A and 3B, the mounting board 2 is composed of a firstrigid board 21, a second rigid board 22, a third rigid board 23, afourth rigid board 24, and a fifth rigid board 25 disposed away fromeach other, and a flexible board 26 for connecting these rigid boards.

It should be noted that hereinafter surfaces of the rigid boards 21through 25 shown in FIG. 3A are referred to as “obverse-side mountingsurfaces,” and surfaces shown in FIG. 3B are referred to as“reverse-side mounting surfaces” for the sake of convenience ofexplanation.

The flexible board 26 has a first connection section 261 for connectingthe first rigid board 21 and the third rigid board 23, a secondconnection section 262 for connecting the second rigid board 22 and thethird rigid board 23, a third connection section 263 for connecting thethird rigid board 23 and the fourth rigid board 24, and a fourthconnection section 264 for connecting the fourth rigid board 24 and thefifth rigid board 25. Each of the connection sections 261 through 264has flexibility, and therefore easily makes bending deformation in thesurface direction.

The mounting board 2 is capable of changing the posture of the rigidboards 21 through 25 by bending the connection sections 261 through 264of the flexible board 26. Specifically, by bending the connectionsections 261 through 264 so that obverse side mounting surfaces 211through 251 of the respective rigid boards 21 through 25 face inward,the mounting board 2 can be deformed to have a cuboid shape in which therigid boards adjacent to each other are perpendicular to each other. Inthis state, assuming that the third rigid board 23 forms a lowersurface, the fourth rigid board 24 forms an upper surface, and thefirst, second, and fifth rigid boards 21, 22, and 25 respectively formside surfaces.

As described above, by constituting the mounting board 2 with therigid-flexible board, it is possible to easily deform the mounting board2, and therefore, it becomes easy to fix the mounting board 2 to amounting member 3. Further, since the rigid boards 21 through 25 areconnected to each other in a lump by the connection sections 261 through264, also in this regard, the fixation of the mounting board 2 to themounting member 3 can be performed easily and smoothly. Further, since aplurality of rigid boards are provided, freedom of arrangement of theelectronic components 7 increases.

Further, by mounting the electronic components 7 on the hard rigidboard, unwanted vibration of the electronic components 7 (in particularthe angular velocity sensors 711 through 713, an acceleration sensor 72)can be suppressed, and thus the detection accuracy of the sensor device1 is improved. Further, the electronic components 7 are easy to bemounted on the mounting board 2. Still further, the parallelism of theelectronic components 7 can easily be achieved, and in particular, theangular velocity sensors 711 through 713 can easily be set to havedesired postures, and the postures can be kept. Further, the electroniccomponents 7 can also be mounted at high density.

Here, in the present embodiment, the third rigid board 23 has a cutoutsection 23 c, a cutout section 23 d, and a cutout section 23 e eachopened in an edge (an outer periphery) thereof. The cutout section 23 cis formed to have a step with respect to the upper side of the thirdrigid board 23 in FIG. 3A, and the first connection section 261 extendsfrom the cutout section 23 c. Further, the cutout section 23 d is formedto have a step with respect to the left side of the third rigid board 23in FIG. 3A, and the second connection section 262 extends from thecutout section 23 d. Further, the cutout section 23 e is formed to havea step with respect to the right side of the third rigid board 23 inFIG. 3A, and the third connection section 263 extends from the cutoutsection 23 e.

By providing the cutout section 23 c to the third rigid board 23, it ispossible to easily make the first connection section 261 have thebending deformation in the vicinity of (on the third rigid board 23 sideof) a connection portion with the third rigid board 23, and further, thecurvature radius of the bending deformation can be kept relativelylarge. Further, excessive projection of the first connection section 261is prevented, and thus downsizing of the sensor device 1 can beachieved. Substantially the same advantage can be achieved with respectto the cutout sections 23 d, 23 e.

Further, in the present embodiment, the fourth rigid board 24 has acutout section 24 c, and a cutout section 24 d each opened in an edge(an outer periphery) thereof. The cutout section 24 c is formed to havea step with respect to the left side of the fourth rigid board 24 inFIG. 3A, and the third connection section 263 extends from the cutoutsection 24 c. Similarly, the cutout section 24 d is formed to have astep with respect to the lower side of the fourth rigid board 24 in FIG.3A, and the fourth connection section 264 extends from the cutoutsection 24 d.

By providing the cutout section 24 c to the fourth rigid board 24, it ispossible to easily make the third connection section 263 have thebending deformation in the vicinity of (on the fourth rigid board 24side of) a connection portion with the fourth rigid board 24, andfurther, the curvature radius of the bending deformation can be keptrelatively large. Further, excessive projection of a bent portion fromthe outer periphery of the fourth rigid board 24 is prevented, and thusdownsizing of the sensor device 1 can be achieved. Substantially thesame advantage can be achieved with respect to the cutout section 24 d.

The mounting board 2 is hereinabove explained. It should be noted thateach of the rigid boards 21 through 25, and the flexible board 26 of themounting board 2 is provided with conductor patterns not shown, and theplurality of electronic components 7 are electrically connected in anappropriate manner via the conductor patterns.

Further, the mounting board 2 is provided with a ground layer not shown,and the ground layer exerts a function of blocking an external magneticfield. Therefore, in the condition of being fixed to the casing 10, itis possible to eliminate the influence of the external magnetic field(external noise) from the outside of the sensor device 1 with respect tothe electronic components 7 (i.e., the electronic components 7 mountedon the obverse side mounting surfaces 211 through 251) located insidethe mounting board 2.

Electronic Components 7

As shown in FIGS. 3A and 3B, on the mounting board 2, there is mountedthe plurality of electronic components 7.

On the mounting board 2, there are mounted as the electronic components7 three angular velocity sensors (sensor components) 711 through 713 ofa uniaxial detection type, the acceleration sensor (a sensor component)72 of a triaxial detection type, a power supply circuit 73 for driving avariety of electronic components, an amplifier circuit 74 for amplifyingoutput signals from the sensor components 711 through 713, and 72, ananalog/digital converter circuit 75 for converting analog signals thusamplified by the amplifier circuit 74 into digital signals, amicrocontroller 76 for performing desired control, a nonvolatile memory77 such as an EEPROM, a direction sensor (a magnetic sensor) 78 fordetecting the direction, and a connector (an interface connector) 79 foroutputting signals. It should be noted that the electronic components 7to be mounted thereon are not limited thereto, but it is possible toarbitrarily mount any components corresponding to the purpose.

Hereinafter, the arrangement of the electronic components 7 will bedescribed in detail.

First Rigid Board 21

On the obverse side mounting surface 211 of the first rigid board 21,there is mounted the angular velocity sensor 711.

Second Rigid Board 22

On the obverse side mounting surface 221 of the second rigid board 22,there is mounted the angular velocity sensor 712.

Third Rigid Board 23

On the obverse side mounting surface 231 of the third rigid board 23,there are mounted the power supply circuit 73, the amplifier circuit 74,and the analog/digital converter circuit 75, and on a reverse sidemounting surface 232, there are mounted the angular velocity sensor 713and the acceleration sensor 72.

The analog/digital converter circuit 75 is larger in size than the otherelectronic components 7 (the power supply circuit 73 and the amplifiercircuit 74) mounted on the obverse side mounting surface 231. Therefore,it is preferable to dispose the analog/digital converter circuit 75 at acenter portion of the obverse side mounting surface 231. Thus, it ispossible to effectively use the analog/digital converter circuit 75 as areinforcement member for reinforcing the rigidity of the third rigidboard 23. Therefore, the unwanted vibration due to the flexuraldeformation of the third rigid board 23 can be suppressed, the unwantedvibration can be prevented from being transmitted to the angularvelocity sensors 711 through 713, and therefore the accuracy of thedetection of the angular velocity by the angular velocity sensors 711through 713 (in particular the angular velocity sensor 713 mounted onthe third rigid board 23) is improved.

Further, the angular velocity sensor 713 and the acceleration sensor 72are preferably disposed in the vicinity of an edge portion of theobverse side mounting surface 231. As described later, the third rigidboard 23 is fixed to the pedestal 4 at the edge portion thereof via anadhesive. Therefore, it is hard for the edge portion of the third rigidboard 23 to be deformed, and therefore the unwanted vibration isdifficult to occur. Therefore, by disposing the angular velocity sensor713 and the acceleration sensor 72 at such places, the angular velocityand the acceleration can more accurately be detected.

Further, by mounting the angular velocity sensor 713 and theacceleration sensor 72 on the reverse side mounting surface 232, it ispossible to elongate the distance from the microcontroller 76 in thecondition in which the mounting board 2 is fixed to the casing 10.Further, it is possible to make the ground layer provided to the thirdrigid board 23 be located between the angular velocity sensor 713 andthe acceleration sensor 72, and the microcontroller 76. Therefore, it ispossible to prevent radiation noise generated from the microcontroller76 from exerting a harmful influence on the angular velocity sensor 713and the acceleration sensor 72 to thereby improve the detection accuracyof the angular velocity sensor 713 and the acceleration sensor 72.

Fourth Rigid Board 24

On the obverse side mounting surface 241 of the fourth rigid board 24,there is mounted the microcontroller 76, and on a reverse side mountingsurface 242, there are mounted the nonvolatile memory 77 and thedirection sensor 78.

The microcontroller 76 is larger in size than the other electroniccomponents 7 (the nonvolatile memory 77 and the direction sensor 78)mounted on the fourth rigid board 24. Therefore, it is preferable todispose the microcontroller 76 at a center portion of the obverse sidemounting surface 241. Thus, it is possible to effectively use themicrocontroller 76 as a reinforcement member for reinforcing therigidity of the fourth rigid board 24. Therefore, the unwanted vibrationdue to the flexural deformation of the fourth rigid board 24 can besuppressed, and the unwanted vibration can be prevented from beingtransmitted to the angular velocity sensors 711 through 713, andtherefore the accuracy of the detection of the angular velocity by theangular velocity sensors 711 through 713 is improved.

Further, by mounting the direction sensor 78 on the mounting surfaceopposite to the surface on which the microcontroller 76 is mounted, theradiation noise generated from the microcontroller 76 can be blocked bythe ground layer of the fourth rigid board 24, and therefore, theradiation noise (the magnetic field) can effectively be prevented fromexerting a harmful influence on the direction sensor 78. Therefore, thedetection accuracy of the direction sensor 78 can be improved.

Fifth Rigid Board 25

On a reverse side mounting surface 252 of the fifth rigid board 25,there is mounted the connector 79.

Hereinabove, the arrangement of the electronic components 7 is describedin detail.

In the mounting board 2, an analog circuit composed of the power supplycircuit 73, the amplifier circuit 74, the analog/digital convertercircuit 75, and so on is provided to the third rigid board 23, and adigital circuit composed of the microcontroller 76, the nonvolatilememory 77, and so on is provided to the fourth rigid board 24. Byforming the analog circuit and the digital circuit on the respectiverigid boards separated from each other as described above, thegeneration and the transmission of the noise can effectively besuppressed, and thus the detection accuracy of the sensor device 1 isfurther enhanced.

The angular velocity sensors 711 through 713 are not particularlylimited providing the angular velocity can be detected, and knownuniaxial detection type of angular velocity sensors can be usedtherefor. As such angular velocity sensors 711 through 713, a sensorhaving a vibrator element 5 shown in FIG. 4, for example, can be used.

The vibrator element 5 is made of a quartz crystal (a piezoelectricmaterial). Further, the vibrator element 5 has a base section 51, a pairof detecting vibrator arms 52, 53 extending in a vertical direction of asheet of the drawing from both sides of the base section 51, a pair ofconnection arms 54, 55 extending in a lateral direction of the sheetfrom both sides of the base section 51, and pairs of driving vibratorarms 56, 57, 58, and 59 extending in the vertical direction of the sheetfrom both sides of respective tip portions of the connection arms 54,55. Further, a surface of each of the detecting vibrator arms 52, 53 isprovided with a detecting electrode (not shown), and a surface of eachof the driving vibrator arms 56, 57, 58, and 59 is provided with adriving electrode (not shown).

In such a vibrator element 5, in the condition in which the drivingvibrator arms 56, 58 and the driving vibrator arms 57, 59 are made tovibrate by applying a voltage to the driving electrodes so as to repeatto come closer to and get away from each other, when an angular velocityω around a normal line A (a detection axis A) of the vibrator element 5is applied, the Coriolis force is applied to the vibrator element 5, andthe vibration of the detecting vibrator arms 52, 53 is excited. Then, bydetecting the distortion in the detecting vibrator arms 52, 53, which iscaused by the vibration of the detecting vibrator arms 52, 53, by thedetecting electrodes, the angular velocity applied to the vibratorelement 5 can be obtained.

The angular velocity sensors 711 through 713 each having theconfiguration described above are mounted on the first through thirdrigid boards 21 through 23, respectively, so that the thicknessdirection of the rigid board corresponds to the detection axis.

Casing

As shown in FIG. 2, the casing 10 has the mounting member 3, thepedestal (a first lid member) 4, and a lid member (a second lid member)8. In other words, the mounting member 3 constitutes a part of thecasing 10. Since the number of components of the sensor device 1 can bereduced by using the mounting member 3 as the part of the casing asdescribed above, the downsizing of the sensor device 1 can be achieved.

Such a casing 10 as described above has a fixation surface (a firstfixation surface) 101 for fixing the first rigid board 21, a fixationsurface (a second fixation surface) 102 for fixing the second rigidboard 22, a fixation surface (a third fixation surface) 103 for fixingthe third rigid board 23, a fixation surface (a fourth fixation surface)104 for fixing the fourth rigid board 24, and a fixation surface (afifth fixation surface) 105 for fixing the fifth rigid board 25.

Hereinafter, the mounting member 3, the pedestal 4, and the lid member 8will sequentially be explained.

Mounting Member

As shown in FIG. 2, the mounting member 3 has a main body 31, and athrough hole 32 opened in an upper surface and a lower surface of themain body 31. A space in the through hole 32 functions as a housingspace for housing the electronic components 7.

In the present embodiment, the outer shape of the main body 31 in thex-y plan view is a rectangle. Further, the upper surface and the lowersurface are both planes parallel to the x-y plane. Further, the throughhole 32 extends in the z-axis direction and has a roughly rectangularlateral cross-sectional shape.

An inner surface 33 exposed to the through hole 32 is composed of a pairof planes 331, 333 parallel to the y-z plane and a pair of planes 332,334 parallel to the x-z plane. Among these four planes 331 through 334,the plane 331 constitutes the fixation surface 101, the plane 332constitutes the fixation surface 102, and the plane 333 constitutes thefixation surface 105.

As shown in FIG. 2, to the fixation surface 101, there is fixed thefirst rigid board 21 with the reverse side mounting surface 212 facingthe fixation surface 101. Thus, the angular velocity sensor 711 is fixedindirectly to the fixation surface 101 via the first rigid board 21.Since the fixation surface 101 is the plane parallel to the y-z plane asdescribed above, in the state in which the first rigid board 21 is fixedto the fixation surface 101, the detection axis of the angular velocitysensor 711 becomes parallel to the x axis. As described above, only byfixing the first rigid board 21 to the fixation surface 101, positioningof the angular velocity sensor 711 with respect to the casing 10 caneasily be performed.

Further, by locating the angular velocity sensor 711 on the inner sideof the first rigid board 21, the external magnetic field can be blockedby the ground layer provided to the first rigid board 21, and therefore,the influence of the external magnetic field is reduced, and thus thedetection accuracy of the angular velocity sensor 711 is improved.

Although the method of fixing the first rigid board 21 to the fixationsurface 101 is not particularly limited, it is preferable to use both offixation with an adhesive and fixation with screws. Thus, the fixationof the first rigid board 21 to the fixation surface 101 can surely beperformed. Further, since a layer of the adhesive intervenes between themounting member 3 and the first rigid board 21, the adhesive absorbs andeases the vibration transmitted from the mounting member 3 to therebysuppress the unwanted vibration of the first rigid board 21. As aresult, the detection accuracy of the sensor device 1 is furtherimproved.

As shown in FIG. 2, to the fixation surface 102, there is fixed thesecond rigid board 22 with a reverse side mounting surface 222 facingthe fixation surface 102. Thus, the angular velocity sensor 712 is fixedindirectly to the fixation surface 102 via the second rigid board 22.Since the fixation surface 102 is the plane parallel to the x-z plane asdescribed above, in the state in which the second rigid board 22 isfixed to the fixation surface 102, the detection axis of the angularvelocity sensor 712 becomes parallel to the y axis. As described above,only by fixing the second rigid board 22 to the fixation surface 102,positioning of the angular velocity sensor 712 with respect to thecasing 10 can easily be performed.

Further, by locating the angular velocity sensor 712 on the inner sideof the second rigid board 22, the external magnetic field can be blockedby the ground layer provided to the second rigid board 22, andtherefore, the influence of the external magnetic field is reduced, andthus the detection accuracy of the angular velocity sensor 712 isimproved.

Although the method of fixing the second rigid board 22 to the fixationsurface 102 is not particularly limited, it is preferable to use both offixation with an adhesive and fixation with screws. Thus, the fixationof the second rigid board 22 to the fixation surface 102 can surely beperformed. Further, since a layer of the adhesive intervenes between themounting member 3 and the second rigid board 22, the adhesive absorbsand eases the vibration transmitted from the mounting member 3 tothereby suppress the unwanted vibration of the second rigid board 22. Asa result, the detection accuracy of the sensor device 1 is furtherimproved.

As shown in FIG. 2, to the fixation surface 105, there is fixed thefifth rigid board 25 with the reverse side mounting surface 252 facingthe fixation surface 105. Further, the mounting member 3 is providedwith a through hole 35 penetrating the fixation surface 105 and an outerperipheral surface, and the fifth rigid board 25 is fixed to thefixation surface 105 with the connector 79 inserted in the through hole35. Thus, the connector 79 is exposed to the outside of the sensordevice 1 via the through hole 35, and an output of signals from thesensor device 1 can easily be achieved. It should be noted that it ispreferable for the fifth rigid board 25 to be fixed to the fixationsurface 105 so as to cover an opening of the through hole 35. Thus,infiltration of dust and so on into the casing can be prevented tothereby keep the reliability of the sensor device 1.

Although the method of fixing the fifth rigid board 25 to the fixationsurface 105 is not particularly limited, it is preferable to use both offixation with an adhesive and fixation with screws. Thus, the fixationof the fifth rigid board 25 to the fixation surface 105 can surely beperformed. Further, since a layer of the adhesive intervenes between themounting member 3 and the fifth rigid board 25, the adhesive absorbs andeases the vibration transmitted from the mounting member 3 to therebysuppress the unwanted vibration of the fifth rigid board 25. As aresult, the detection accuracy of the sensor device 1 is furtherimproved.

Although a constituent material of such a mounting member 3 is notparticularly limited, a material with a damping property is preferablyused. Thus, the unwanted vibration of the mounting member 3 can besuppressed to thereby improve the detection accuracy of the angularvelocity sensors 711 through 713 and so on. As such a material asdescribed above, there can be cited various types of damping alloys suchas a magnesium alloy, an iron alloy, a copper alloy, a manganese alloy,and a Ni—Ti alloy.

Pedestal 4

The pedestal 4 is fixed to the mounting member 3 so as to block a loweropening of the mounting member 3. The method of fixing the pedestal 4 tothe mounting member 3 is not particularly limited, and the fixationmethod of using an adhesive, for example, can be used.

Such a pedestal 4 has a plate-like shape having the thickness directioncorresponding to the z-axis direction, and has a lower surface and anupper surface 41 parallel to the x-y plane. Further, the upper surface41 constitutes the fixation surface 103 for fixing the third rigid board23.

As shown in FIG. 2, to the fixation surface 103, there is fixed thethird rigid board 23 with the reverse side mounting surface 232 facingthe fixation surface 103. Thus, the angular velocity sensor 713 is fixedindirectly to the fixation surface 103 via the third rigid board 23.Since the fixation surface 103 is the plane parallel to the x-y plane asdescribed above, in the state in which the third rigid board 23 is fixedto the fixation surface 103, the detection axis of the angular velocitysensor 713 becomes parallel to the z axis. As described above, only byfixing the third rigid board 23 to the fixation surface 103, positioningof the angular velocity sensor 713 with respect to the casing 10 caneasily be performed.

Further, the pedestal 4 has a recessed section 42 opened in the fixationsurface 103. The recessed section 42 is opened in a center portion ofthe fixation surface 103 except an edge portion thereof, and is notopened in a side surface of the pedestal 4. In other wards, the recessedsection 42 has a trough shape surrounded by sidewalls in the peripherythereof.

In the condition of fixing the third rigid board 23 to the fixationsurface 103, the angular velocity sensor 713 and the acceleration sensor72 mounted on the reverse side mounting surface 232 of the third rigidboard 23 are located in the recessed section 42. In other words, therecessed section 42 forms a clearance for preventing the angularvelocity sensor 713 and the acceleration sensor 72 from having contactwith the pedestal 4. By forming such a recessed section 42 as describedabove, a space of the pedestal 4 can be used effectively to therebyachieve downsizing (low-profiling, reduction in height) of the sensordevice 1.

Further, the recessed section 42 is filled with an infill 9, and a gapbetween the pedestal 4 and the third rigid board 23 is filled with theinfill 9. Thus, the third rigid board 23 (the angular velocity sensor713, the acceleration sensor 72) and the connection sections 261, 262,and 263 extending from the third rigid board 23 are fixed, and thus theunwanted vibration can effectively be prevented from occurring in thethird rigid board 23. Therefore, the detection accuracy of the sensordevice 1 is improved.

As a constituent material of the infill 9, those having an insulatingproperty are preferable. The material is not particularly limited, andthere can be cited as the material, for example, polyolefin such aspolyethylene, or polypropylene, ethylene-propylene copolymer, polyvinylchloride, polystyrene, polyamide, polyimide, polycarbonate,poly-(4-methylpentene-1), ionomer, acrylic resin,polymethylmethacrylate, acrylonitrile-butadiene-styrene copolymer (ABSresin), acrylonitrile-styrene copolymer (AS resin), butadiene-styrenecopolymer, polyester such as polyethylene terephthalate (PET), orpolybutylene terephthalate (PBT), polyether, polyetherketone (PEK),polyether ether ketone (PEEK), polyetherimide, polyacetal (POM),polyphenylene oxide, polysulfone, polyethersulfone, polyphenylenesulfide, polyarylate, aromatic polyester (liquid crystal polymer),fluorinated resin such as polytetrafluoroethylene or polyvinylidenefluoride, epoxy resin, phenol resin, urea resin, melamine resin,silicone resin, polyurethane resin, and so on, copolymers, polymerblends, and polymer alloys having any one of these compounds as aprimary constituent, and these materials can be used alone or incombination.

The constituent material of such a pedestal 4 is not particularlylimited, and substantially the same materials as those of the mountingmember 3 can be cited for example.

Lid Member 8

The lid member 8 is fixed to the mounting member 3 so as to block anupper opening of the mounting member 3. The method of fixing the lidmember 8 to the mounting member 3 is not particularly limited, and thefixation method of using an adhesive, for example, can be used.

Such a lid member 8 as described above has a plate-like shape having thethickness direction corresponding to the z-axis direction, and has alower surface 81 parallel to the x-y plane. The lower surface 81constitutes the fixation surface 104 for fixing the fourth rigid board24.

As shown in FIG. 2, to the fixation surface 104, there is fixed thefourth rigid board 24 with the reverse side mounting surface 242 facingthe fixation surface 104. Since the fixation surface 104 is a planeparallel to the x-y plane as described above, the rigid board 24 fixedto the fixation surface 104 is opposed to the third rigid board 23 inthe z-axis direction, and at the same time disposed in parallel to thethird rigid board 23. By disposing the third and fourth rigid boards 23,24 so as to overlap each other in the z-axis direction, downsizing ofthe sensor device 1 in the x-y plan view can be achieved. In addition,by making the third and fourth rigid boards 23, 24 parallel to eachother, the length in the z-axis direction (the height) of the sensordevice 1 can be reduced, and in this regard, downsizing of the sensordevice 1 can also be achieved.

Further, the lid member 8 has a recessed section 82 opened in thefixation surface 104. The recessed section 82 is opened in a centerportion of the fixation surface 104 except an edge portion thereof, andis not opened in a side surface of the lid member 8. In other wards, therecessed section 82 has a trough shape surrounded by sidewalls in theperiphery thereof.

In the condition of fixing the fourth rigid board 24 to the fixationsurface 104, the nonvolatile memory 77 and the direction sensor 78mounted on the reverse side mounting surface 242 of the fourth rigidboard 24 are located in the recessed section 82. In other words, therecessed section 82 forms a clearance for preventing the nonvolatilememory 77 and the direction sensor 78 from having contact with the lidmember 8. By forming such a recessed section 82 as described above, aspace of the lid member 8 can be used effectively, and thus downsizing(low-profiling, reduction in height) of the sensor device 1 can beachieved. It should be noted that it is also possible to fill such arecessed section 82 as described above with the infill 9 as in the caseof the recessed section 42 described above.

A constituent material of such a lid member 8 is not particularlylimited, and substantially the same materials as those of the mountingmember 3 can be cited for example.

Hereinabove, the sensor device 1 is described in detail.

According to such a sensor device 1 as described above, since themounting board 2 is fixed directly to the casing 10, the number ofcomponents is small, and the downsizing can be achieved accordingly.Further, since the positioning of the rigid boards 21 through 25 can beperformed with ease and accuracy, excellent detection performance andreliability can be exerted.

It should be noted that when mounting the sensor device 1 on the circuitboard such as a motherboard, by using two side surfaces 4 a, 4 b of thepedestal 4 perpendicular to each other as the reference, it is possibleto easily point the detection axes of the angular velocity sensors 711,712 to the desired directions. Specifically, the side surface 4 a is aplane parallel to the detection axis of the angular velocity sensor 712,and the side surface 4 b is a plane parallel to the detection axis ofthe angular velocity sensor 711. Therefore, by performing thepositioning with respect to the circuit board using the side surfaces 4a, 4 b as the reference, it is possible to point the detection axes ofthe angular velocity sensors 711, 712 to the desired directions withease and accuracy.

Second Embodiment

Then, a sensor device according to a second embodiment of the inventionwill be explained.

FIG. 5 is a cross-sectional view showing the sensor device according tothe second embodiment of the invention.

Hereinafter, the second embodiment will be described with a focus mainlyon differences from the first embodiment described above, andexplanations regarding substantially the same matters will be omitted.The sensor device according to the present embodiment is substantiallythe same as the sensor device according to the first embodiment exceptthat the configuration of the casing is different. It should be notedthat the constituents identical to those of the first embodimentdescribed above are denoted by the same reference symbols.

As shown in FIG. 5, a casing 1 OA provided to the sensor device 1according to the present embodiment has a mounting member 3A and the lidmember 8. In other words, in the present embodiment, the pedestal 4 ofthe first embodiment described above is formed integrally with themounting member 3.

The mounting member 3A has a main body 31A, and a recessed section 32Aopened in an upper surface of the main body 31A. A space in the recessedsection 32A functions as a housing space for housing the electroniccomponents 7. The recessed section 32A has a rectangular lateralcross-sectional shape.

An inner surface 33A exposed to the recessed section 32A is composed ofa pair of planes 331A, 333A parallel to the y-z plane, a pair of planes332A, 334A parallel to the x-z plane, and a plane 335A parallel to thex-y plane. Among these five planes 331A through 335A, the plane 331Aconstitutes the fixation surface 101, the plane 332A constitutes thefixation surface 102, the plane 333A constitutes the fixation surface105, and the plane 335A constitutes the fixation surface 103.

To the fixation surface 101, there is fixed the first rigid board 21with a reverse side mounting surface 212 facing the fixation surface101. Thus, the detection axis of the angular velocity sensor 711 becomesparallel to the x axis.

To the fixation surface 102, there is fixed the second rigid board 22with the reverse side mounting surface 222 facing the fixation surface102. Thus, the detection axis of the angular velocity sensor 712 becomesparallel to the y axis.

To the fixation surface 103, there is fixed the third rigid board 23with the reverse side mounting surface 232 facing the fixation surface103. Thus, the detection axis of the angular velocity sensor 713 becomesparallel to the z axis. Further, the mounting member 3A has a recessedsection 39A opened in the fixation surface 103. The recessed section 39Ais opened at a center portion of the fixation surface 103 except an edgeportion thereof, and in the condition of fixing the third rigid board 23to the fixation surface 103, the angular velocity sensor 713 and theacceleration sensor 72 are located in the recessed section 39A. Further,the recessed section 39A is filled with the infill 9.

To the fixation surface 105, there is fixed the fifth rigid board 25with the reverse side mounting surface 252 facing the fixation surface105. Further, the mounting member 3A is provided with the through hole35 penetrating the fixation surface 105 and the outer peripheralsurface, and the fifth rigid board 25 is fixed to the fixation surface105 with the connector 79 inserted in the through hole 35.

According also to the second embodiment described hereinabove,substantially the same advantage as in the first embodiment describedabove can be obtained.

Third Embodiment

Then, a sensor device according to a third embodiment of the inventionwill be explained.

FIG. 6 is a cross-sectional view of the sensor device according to thethird embodiment of the invention, FIGS. 7A and 7B are developmentdiagrams of a mounting board provided to the sensor device shown in FIG.6, and FIG. 8 is a cross-sectional view showing a modified example ofthe sensor device shown in FIG. 6.

Hereinafter, the third embodiment will be described with a focus mainlyon differences from the embodiments described above, and explanationsregarding substantially the same matters will be omitted.

The sensor device according to the present embodiment is substantiallythe same as the sensor device according to the first embodiment exceptthat mounting positions of the angular velocity sensors with respect tothe mounting board 2 are different. It should be noted that theconstituents identical to those of the first embodiment described aboveare denoted by the same reference symbols.

As shown in FIGS. 7A and 7B, in the mounting board 2 according to thepresent embodiment, the angular velocity sensor 711 is mounted on thereverse side mounting surface 212 of the first rigid board 21, and theangular velocity sensor 712 is mounted on the reverse side mountingsurface 222 of the second rigid board 22.

Further, as shown in FIG. 6, the first mounting board 21 is fixed to thefixation surface 101 with the angular velocity sensor 711 located on thefixation surface 101 side and directly fixed to the fixation surface 101with an adhesive or the like. Similarly, the second mounting board 22 isfixed to the fixation surface 102 with the angular velocity sensor 712located on the fixation surface 102 side and directly fixed to thefixation surface 102 with an adhesive or the like.

It should be noted that as a modified example of the present embodiment,as shown in FIG. 8, it is also possible for the fixation surface 101 tohave a recessed section 101 a at a position corresponding to the angularvelocity sensor 711, and house a part of the angular velocity sensor 711in the recessed section 101 a. The depth of the recessed section 101 ais set to be slightly smaller than the thickness of the angular velocitysensor 711 in order for preventing the first mounting board 21 and thefixation surface 101 from having contact with each other.

Similarly, it is also possible for the fixation surface 102 to have arecessed section 102 a at a position corresponding to the angularvelocity sensor 712, and house a part of the angular velocity sensor 712in the recessed section 102 a. The depth of the recessed section 102 ais set to be slightly smaller than the thickness of the angular velocitysensor 712 in order for preventing the second mounting board 22 and thefixation surface 102 from having contact with each other.

By providing the recessed sections 101 a, 102 a to the fixation surfaces101, 102 as described above, the space of the mounting member 3 caneffectively be used, and the downsizing of the sensor device 1 can beachieved.

According also to the third embodiment described hereinabove,substantially the same advantage as in the first embodiment describedabove can be obtained.

2. Electronic Apparatus

The sensor device 1 described above can be incorporated in a variety ofelectronic apparatuses. The electronic apparatus according to anembodiment of the invention equipped with the sensor device 1 willhereinafter be described. FIG. 9 is a diagram showing an example of aconfiguration of an electronic apparatus 500 equipped with the sensordevice 1. The electronic apparatus 500 is not particularly limited, andthere can be cited as the electronic apparatus, for example, a digitalcamera, a video camera, a car navigation system, a cellular phone, amobile PC, a robot, a gaming machine, and a gaming controller.

The electronic apparatus 500 shown in FIG. 9 has a sensor module 510including the sensor device 1, a processing section 520, a memory 530,an operating section 540, and a display section 550. These constituentsare connected to each other via a bus 560. The processing section (e.g.,a CPU and an MPU) 520 performs control of the sensor module 510 and soon and the overall control of the electronic apparatus 500. Further, theprocessing section 520 performs a process based on angular velocityinformation detected by the sensor module 510. For example, theprocessing section 520 performs a process for blurring correction,posture control, and GPS autonomous navigation based on the angularvelocity information. The memory 530 stores a control program and avariety of data, and further, functions as a working area and a datastorage area. The operating section 540 is for a user to operate theelectronic apparatus 500. The display section 550 is for displaying avariety of information to the user.

Although the sensor device and the electronic apparatus according to theinvention are hereinabove described based on the embodiments shown inthe accompanying drawings, the invention is not limited thereto, but theconfiguration of each of the constituents can be replaced with onehaving an arbitrary configuration with an equivalent function.

Further, although in the embodiments described above there is explainedthe configuration of mounting the three angular velocity sensors on themounting board, the number of angular velocity sensors is not limitedthereto, and can be one or two. Further, the number of rigid boards canalso be changed in accordance with the number of angular velocitysensors.

Further, although in the embodiments described above the mounting boardis formed of the rigid-flexible board, the configuration of the mountingboard is not limited thereto, and it is also possible to configure themounting board with a plurality of rigid boards not connected to eachother. In this case, it is possible to electrically connect the rigidboards to each other using connectors and so on after fixing the rigidboards to the mounting member.

Further, although in the embodiments described above the configurationof fixing the electronic components mounted on the mounting board to thecasing is explained, the configuration is not limited thereto, and it isalso possible to eliminate the mounting board, and directly fix theelectronic components to the casing. In this case, it is possible toseparately form wires or the like for electrically connecting theelectronic components to each other.

What is claimed is:
 1. A sensor device having an X-axis, a Y-axis, and aZ-axis orthogonal to each other, the sensor device comprising: a casingincluding: a main body having: a base having front and rear surfacesopposite to each other, the front and rear surfaces of the baserespectively extending in a direction orthogonal to the Z-axis; a firstside wall being connected to a first edge of the base, the first sidewall extending in a direction orthogonal to the X-axis, the first edgeextending in a direction along the Y-axis; and a second side wall beingconnected to a second edge of the base, the second side wall extendingin a direction orthogonal to the Y-axis, the second edge extending in adirection along the X-axis; and a lid closing an inner space surroundedby the base and the first and second side walls of the main body; amounting board housed in the inner space of the casing, the mountingboard including: a first board having front and rear surfaces oppositeto each other, the front and rear surfaces of the first boardrespectively extending in a direction orthogonal to the X-axis, thefirst board facing the first side wall of the main body; a second boardhaving front and rear surfaces opposite to each other, the front andrear surfaces of the second board respectively extending in a directionorthogonal to the Y-axis, the second board facing the second side wallof the main body; a third board having front and rear surfaces oppositeto each other, the front and rear surfaces of the third boardrespectively extending in a direction orthogonal to the Z-axis; a fourthboard having front and rear surfaces opposite to each other, the frontand rear surfaces of the fourth board respectively extending in adirection orthogonal to the Z-axis; and a flexible board extending froma first outer periphery of the third board towards a second outerperiphery of the fourth board; a first gyro sensor mounted on the firstboard, the first gyro sensor being configured to detect an angularvelocity around the X-axis; a second gyro sensor mounted on the secondboard, the second gyro sensor being configured to detect an angularvelocity around the Y-axis; and a third gyro sensor mounted on the thirdboard, the third gyro sensor being configured to detect an angularvelocity around the Z-axis, wherein the third board has a cutout at aside thereof, and the flexible board extends towards the cutout of thethird board.
 2. The sensor device according to claim 1, furthercomprising: an acceleration sensor mounted on the third board, theacceleration sensor being configured to detect an acceleration in adirection along each of the X-axis, the Y-axis, and the Z-axis.
 3. Thesensor device according to claim 1, wherein the base and the first andsecond side walls of the main body are integrated with each other. 4.The sensor device according to claim 3, wherein the first gyro sensor ismounted at a first position on the first board, and the first positionis located at an opposite side of the first board with respect to thefirst side wall of the main body, the second gyro sensor is mounted at asecond position on the second board, and the second position is locatedat an opposite side of the second board with respect to the second sidewall of the main body, and the third gyro sensor is mounted at a thirdposition on the third board, and the third position is located at anopposite side of the third board with respect to the base of the mainbody.
 5. The sensor device according to claim 4, further comprising: amicrocontroller mounted on the fourth board, wherein the microcontrolleris configured to control the first, second, and third gyro sensors. 6.An electronic apparatus comprising: the sensor device according to claim1; and a processing section configured to sense or output a posture ofthe electronic apparatus in response to an output signal from the sensordevice.
 7. A sensor device having an X-axis, a Y-axis, and a Z-axisorthogonal to each other, the sensor device comprising: a casingincluding: a main body having: a base having front and rear surfacesopposite to each other, the front and rear surfaces of the baserespectively extending in a direction orthogonal to the Z-axis; a firstside wall being connected to a first edge of the base, the first sidewall extending in a direction orthogonal to the X-axis, the first edgeextending in a direction along the Y-axis; and a second side wall beingconnected to a second edge of the base, the second side wall extendingin a direction orthogonal to the Y-axis, the second edge extending in adirection along the X-axis; and a lid closing an inner space surroundedby the base and the first and second side walls of the main body; amounting board housed in the inner space of the casing, the mountingboard including: a first board having front and rear surfaces oppositeto each other, the front and rear surfaces of the first boardrespectively extending in a direction orthogonal to the X-axis, thefirst board facing the first side wall of the main body; a second boardhaving front and rear surfaces opposite to each other, the front andrear surfaces of the second board respectively extending in a directionorthogonal to the Y-axis, the second board facing the second side wallof the main body; a third board having front and rear surfaces oppositeto each other, the front and rear surfaces of the third boardrespectively extending in a direction orthogonal to the Z-axis; a fourthboard having front and rear surfaces opposite to each other, the frontand rear surfaces of the fourth board respectively extending in adirection orthogonal to the Z-axis; and a flexible board extending froma first outer periphery of the third board towards a second outerperiphery of the fourth board; a first gyro sensor mounted on the firstboard, the first gyro sensor being configured to detect an angularvelocity around the X-axis; a second gyro sensor mounted on the secondboard, the second gyro sensor being configured to detect an angularvelocity around the Y-axis; and a third gyro sensor mounted on the thirdboard, the third gyro sensor being configured to detect an angularvelocity around the Z-axis, wherein the fourth board has a cutout at aside thereof, and the flexible board extends towards the cutout of thefourth board.
 8. The sensor device according to claim 7, furthercomprising: an acceleration sensor mounted on the third board, theacceleration sensor being configured to detect an acceleration in adirection along each of the X-axis, the Y-axis, and the Z-axis.
 9. Thesensor device according to claim 7, wherein the base and the first andsecond side walls of the main body are integrated with each other. 10.The sensor device according to claim 7, wherein the first gyro sensor ismounted at a first position on the first board, and the first positionis located at an opposite side of the first board with respect to thefirst side wall of the main body, the second gyro sensor is mounted at asecond position on the second board, and the second position is locatedat an opposite side of the second board with respect to the second sidewall of the main body, and the third gyro sensor is mounted at a thirdposition on the third board, and the third position is located at anopposite side of the third board with respect to the base of the mainbody.
 11. The sensor device according to claim 7, further comprising: amicrocontroller mounted on the fourth board, wherein the microcontrolleris configured to control the first, second, and third gyro sensors. 12.An electronic apparatus comprising: the sensor device according to claim7; and a processing section configured to sense or output a posture ofthe electronic apparatus in response to an output signal from the sensordevice.